#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<math.h>

int main()
{
	double a, b, c, disc, x1, x2;
	scanf(% 1f % 1f % 1f, &a, &b, &c)
		disc = b * b - 4 * a * c;
	if (disc<0)
	{
		printf("this equation has't real roots.\n");

	}

	return 0;
}